Electronic device that receives power from power supply apparatus and method thereof

ABSTRACT

An electronic device includes a connector that includes a first terminal for receiving power from a power supply apparatus, a second terminal, a third terminal, and a fourth terminal; a control unit that controls power received from the power supply apparatus via the first terminal; and a determination unit that determines a power supply capability of the power supply apparatus by using the second terminal or the third terminal and the fourth terminal, wherein the determination unit determines the power supply capability of the power supply apparatus by using the third terminal and the fourth terminal before a predetermined transition occurs in the second terminal.

BACKGROUND Field of the Invention

Aspects of the disclosure generally relate to an electronic device thatreceives power from a power supply apparatus and a method thereof.

Description of the Related Art

According to USB (Universal Serial Bus) standard (USB 3.0 standard, USB2.0 standard, USB BC (Battery Charging) 1.2 standard, or the like)defined before USB Type-C standard, the power supply capability of apower supply apparatus is detectable by using D+ and D− terminals. Inthis specification, USB standard (USB 3.0 standard, USB 2.0 standard,USB BC (Battery Charging) 1.2 standard, or the like) which was definedbefore the USB Type-C standard will be referred to as a “legacystandard”. In a legacy standard, the power supply capability of a powersupply apparatus is determined by using D+ and D− terminals. In the USBType-C standard, the power supply capability of a power supply apparatusis determined by using a CC (Configuration Channel) terminal. Accordingto the USB Type-C standard, a CC voltage (a voltage applied to the CCterminal) indicates which of the three different power supplycapabilities (Default USB, 7.5 W (1.5 A, 5 V), and 15 W (3 A, 5V)) isbeing employed as the power supply capability of the power supplyapparatus. Default USB is a power supply capability defined by a legacystandard. 7.5 W (1.5 A, 5 V) and 15 W (3 A, 5V) are power supplycapabilities defined by the USB Type-C standard. Hence, a powerreceiving apparatus can detect the power supply capability of a powersupply apparatus by the detected CC voltage. If the power supplycapability of the power supply apparatus shifts from 15 W (3 A, 5V) or7.5 W (1.5 A, 5 V) to Default USB, the power receiving apparatus isrequired to operate as a power receiving apparatus conforming to alegacy standard during a predetermined time defined by the USB Type-Cstandard.

Japanese Patent Laid-Open No. 2003-280771 discloses a method ofcontrolling the operation of an electronic device in accordance with thepower supply capability of a power supply apparatus. In Japanese PatentLaid-Open No. 2003-280771, switching of input power supply is performedso as not to exceed the power supply capability of the power supplyapparatus.

A certain amount of time is required for the determination of the powersupply capability of a power supply apparatus which is performed inaccordance with a legacy standard. Hence, there is a possibility thatthe power supply from the power supply apparatus to the power receivingapparatus will be suppressed before the completion of the determinationof the power supply capability of a power supply apparatus which isperformed in accordance with a legacy standard. If power supplied fromthe power supply apparatus to the power receiving apparatus falls belowthe power consumption of the power receiving apparatus, the powerreceiving apparatus may unexpectedly stop its operation.

SUMMARY

According to an aspect of the embodiments, one or more of the problemsdescribed above that occur in an electronic device that operates as apower receiving apparatus can be solved.

According to an aspect of the embodiments, there is provided anelectronic device comprising: a connector that comprises a firstterminal for receiving power from a power supply apparatus, a secondterminal, a third terminal, and a fourth terminal; a control unit thatcontrols power received from the power supply apparatus via the firstterminal; and a determination unit that determines a power supplycapability of the power supply apparatus by using the second terminal orthe third terminal and the fourth terminal, wherein the determinationunit determines the power supply capability of the power supplyapparatus by using the third terminal and the fourth terminal before apredetermined transition occurs in the second terminal.

According to an aspect of the embodiments, there is provided a methodcomprising: starting to receive power from a power supply apparatus viaa first terminal for receiving power from the power supply apparatus;determining a power supply capability of the power supply apparatus byusing a second terminal; and determining, before a predeterminedtransition occurs in the second terminal, the power supply capability ofthe power supply apparatus by using a third terminal and a fourthterminal.

According to an aspect of the embodiments, there is provided anon-transitory storage medium that stores a program causing a computerto execute a method, the method comprising: starting to receive powerfrom a power supply apparatus via a first terminal for receiving powerfrom the power supply apparatus; determining a power supply capabilityof the power supply apparatus by using a second terminal; anddetermining, before a predetermined transition occurs in the secondterminal, the power supply capability of the power supply apparatus byusing a third terminal and a fourth terminal.

Further aspects of the embodiments will become apparent from thefollowing embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram for illustrating an example of components of apower receiving apparatus 100 according to the first embodiment;

FIGS. 2A and 2B are flowcharts for illustrating an example of theoperation of the power receiving apparatus 100;

FIG. 3 is a timing chart for illustrating an example of the operation ofthe power receiving apparatus 100;

FIG. 4 is a table for illustrating the relationship between a CC voltageand power supply capabilities of a power supply apparatus 200; and

FIG. 5 is a view for illustrating the pin assignment of a connectingunit 101.

DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments, features, and aspects of the disclosure will bedescribed below with reference to the drawings. However, aspects of thedisclosure are not limited to the following embodiments.

First Embodiment

FIG. 1 is a block diagram for illustrating an example of components of apower receiving apparatus 100 according to the first embodiment.

The power receiving apparatus 100 is an electronic device that receivespower supplied from a power supply apparatus 200 to which it isconnected via a USB Type-C cable. Although a case in which the powersupply apparatus 200 is an AC adapter (or an AC-USB adapter) thatconverts AC power into DC power will be exemplified in the firstembodiment, the power supply apparatus 200 is not limited to the ACadapter. For example, the power supply apparatus 200 may be a portablebattery or the like. Also, although a case in which the power receivingapparatus 100 is an electronic device that operates as an imagecapturing apparatus (e.g., a digital camera) will be exemplified in thefirst embodiment, the power receiving apparatus 100 is not limited tothe image capturing apparatus.

As shown in FIG. 1, the power receiving apparatus 100 includes aconnecting unit 101, a power source 102, a power receiving and supplyingunit 103, a power control unit 104, a resistor 105, a power supplycapability determination unit 106, a voltage detection unit 107, a BCdevice determination unit 108, and a system control unit 109. However,components of the power receiving apparatus 100 are not limited to thoseshown in FIG. 1.

The connecting unit 101 is a connector (receptacle) conforming to theUSB Type-C standard. The power supply apparatus 200 is connected to theconnecting unit 101 via a USB Type-C cable. The connecting unit 101 hasa pin assignment as shown in FIG. 5. FIG. 5 is a view for illustratingthe pin assignment of the connecting unit 101. The connecting unit 101has a point-symmetric terminal assignment. The connecting unit 101includes at least a VBUS terminal, a GND (ground) terminal, a CC(configuration channel) terminal, a D+ terminal, and a D− terminal. Thepower supply from the power supply apparatus 200 to the power receivingapparatus 100 is performed via the VBUS terminal. A voltage indicatingthe power capability of the power supply apparatus 200 is applied to theCC terminal. Communication conforming to the USB 2.0 standard isperformed via the D+ terminal and the D− terminal. In a case in whichthe power supply apparatus 200 is an electronic device conforming to alegacy standard, the type of power supply apparatus 200 is determinedvia the D+ terminal and the D− terminal. The GND (ground) terminal isconnected to a ground line.

The power source 102 is a chargeable battery (e.g., a lithium ionbattery). The power receiving and supplying unit 103 supplies powerreceived from the power supply apparatus 200 via the VBUS terminal tothe power control unit 104 and the power source 102. The power receivingand supplying unit 103 can charge the power source 102 with powerreceived from the power supply apparatus 200 via the VBUS terminal. Thepower receiving and supplying unit 103 controls the charging of thepower source 102. The power receiving and supplying unit 103 can alsocontrol power to be received (corresponding to power to be received bythe power receiving and supplying unit 103 from the power supplyapparatus 200 via the VBUS terminal of the connecting unit 101) so thatpower to be received will not exceed the power supply capability of thepower supply apparatus 200 which has been determined by the power supplycapability determination unit 106. In this manner, the power receivingand supplying unit 103 can function as a control unit that controlspower to be received from the power supply apparatus 200 via the VBUSterminal. The power control unit 104 can supply power from the powerreceiving and supplying unit 103 to components of the power receivingapparatus 100.

The resistor 105 is a pull-down resistor for lowering the voltage of theCC terminal of the connecting unit 101 to a predetermined voltage level.The predetermined voltage is a voltage defined by the USB Type-Cstandard. One end of the resistor 105 is connected to the CC terminal ofthe connecting unit 101. The other end of the resistor 105 is connectedto the GND terminal of the connecting unit 101. The resistor 105 has apredetermined resistance value defined by the USB Type-C standard.

The voltage detection unit 107 is connected to the CC terminal of theconnecting unit 101. The voltage detection unit 107 detects a CC voltage(corresponding to a voltage applied to the CC terminal of the connectingunit 101) and notifies the power supply capability determination unit106 of information indicating the CC voltage. The BC devicedetermination unit 108 is connected to the D+ terminal and the D−terminal. The BC device determination unit 108 determines the type ofthe power supply apparatus 200 via the D+ terminal and the D− terminal,and notifies the power supply capability determination unit 106 ofinformation related to the determined type. Note that the BC devicedetermination unit 108 determines the type of the power supply apparatus200 in compliance with the USB BC 1.2 standard.

The power supply capability determination unit 106 determines the powersupply capability of the power supply apparatus 200 based on the CCvoltage detected by the voltage detection unit 107. FIG. 4 shows therelationship between CC voltage and the power supply capability of thepower supply apparatus 200. In a case in which the CC voltage is equalto or higher than 0.25 V but lower than 0.66 V, the power supplycapability of the power supply apparatus 200 is Default USB. In a casein which the CC voltage is equal to or higher than 0.66 V but is lowerthan 1.23 V, the power supply capability of the power supply apparatus200 is 7.5 W (1.5 A, 5 V). In a case in which the CC voltage is equal toor higher than 1.23 V but equal to or lower than 2.04 V, the powersupply capability of the power supply apparatus 200 is 15 W (3 A, 5 V).For example, in a case in which the CC voltage is 0.9 V, the powersupply capability determination unit 106 will determine that the powersupply capability of the power supply apparatus 200 is 7.5 W (1.5 A, 5V) because the CC voltage is equal to or higher than 0.66 V but is lowerthan 1.23 V. The power supply capability determination unit 106 can alsoacquire information related to the type of power supply apparatus 200from the BC device determination unit 108, and can determine the powersupply capability of the power supply apparatus 200 based on theinformation related to the type of the power supply apparatus 200. Inaddition, the power supply capability determination unit 106 can notifythe power receiving and supplying unit 103 and the system control unit109 of the information related to the determined power supply capabilityof the power supply apparatus 200.

The system control unit 109 includes a memory that stores programs forcontrolling the components of the power receiving apparatus 100 and aprocessor for controlling the components of the power receivingapparatus 100 by executing corresponding programs stored in the memory.The processor of the system control unit 109 is, for example, a hardwareprocessor. The system control unit 109 can detect power supplied to eachcomponent by the power control unit 104. The system control unit 109 canalso calculate the amount of power supplied to each component by thepower control unit 104 based on the operation state of the powerreceiving apparatus 100. The system control unit 109 can also detect theremaining battery amount of the power source 102. The system controlunit 109 can control the operation of the power receiving apparatus 100so that power supplied from the power control unit 104 to each componentwill be equal to or lower than the power supply capability of the powersupply apparatus 200 determined by the power supply capabilitydetermination unit 106. For example, in a case in which the power supplyapparatus 200 is connected to the connecting unit 101 via a USB Type-Ccable, the system control unit 109 can control the power receivingapparatus 100 so that the power receiving apparatus 100 will operate byusing power received from the power supply apparatus 200 via the VBUSterminal. In this manner, the system control unit 109 restricts thepower consumption of the power receiving apparatus 100 in accordancewith the power supply capability of the power supply apparatus 200.

FIGS. 2A and 2B are flowcharts for illustrating an example of theoperation of the power receiving apparatus 100 according to the firstembodiment.

Step S201 is started when the power supply apparatus 200 is connected tothe connecting unit 101 via a USB Type-C cable. In step S201, the powerreceiving and supplying unit 103 detects the voltage applied to the VBUSterminal of the connecting unit 101. Subsequently, the process of stepS202 is started.

In step S202, the power supply capability determination unit 106determines whether the power supply capability of the power supplyapparatus 200 is Default USB. Whether the power supply capability of thepower supply apparatus 200 is Default USB is determined based on the CCvoltage detected by the voltage detection unit 107. If the CC voltage isequal to or higher than 0.25 V but lower than 0.66 V, the power supplycapability determination unit 106 determines that the power supplycapability of the power supply apparatus 200 is Default USB. In a casein which the power supply capability of the power supply apparatus 200is Default USB, it is defined by the USB Type-C standard that the powerreceiving apparatus 100 will receive power complying with the legacystandard via the VBUS terminal. Hence, if the power supply capability ofthe power supply apparatus 200 is Default USB (YES in step S202), theprocess of step S203 is started. If the power supply capability of thepower supply apparatus 200 is not Default USB, the power supplycapability determination unit 106 will determine the power supplycapability of the power supply apparatus 200 based on the CC voltage.After the power supply capability of the power supply apparatus 200 isdetermined based on the CC voltage (NO in step S202), the process ofstep S208 is started.

In step S203, the BC device determination unit 108 determines the typeof the power supply apparatus 200 via the D+ terminal and the D−terminal. The BC device determination unit 108 supplies, to the powersupply capability determination unit 106, the information related to thetype of the power supply apparatus 200. The power supply capabilitydetermination unit 106 determines the power supply capability of thepower supply apparatus 200 based on the information related to the typeof the power supply apparatus 200. Subsequently, the process of stepS204 is started.

In step S204, the system control unit 109 determines whether theoperation power (corresponding to power supplied to each component fromthe power control unit 104 to operate the power receiving apparatus 100)is higher than the power supply capability of the power supply apparatus200 determined in step S203. If it is determined that the operationpower is higher than the power supply capability of the power supplyapparatus 200 (YES in step S204), the process of step S205 is started.If it is determined that the operation power is equal to or lower thanthe power supply capability of the power supply apparatus 200 (NO instep S204), the process of step S206 is started.

In step S205, the system control unit 109 switches the operation mode orrestricts the functions of the power receiving apparatus 100 so thatoperation power (corresponding to power supplied to each component fromthe power control unit 104 to operate the power receiving apparatus 100)will be equal to or lower than the power supply capability of the powersupply apparatus 200 determined in step S203. Switching from an imagecapturing mode (an operation mode of obtaining an image by an imagecapturing unit (not shown)) to a reproduction mode (an operation mode ofdisplaying an image reproduced from a storage medium on a display unit(not shown)) is an example of operation mode switching. Power suppliedfrom the power control unit 104 to each component of the power receivingapparatus 100 in the reproduction mode is lower than power supplied fromthe power control unit 104 to each component of the power receivingapparatus 100 in the image capturing mode. A state in which some or allof the image capturing functions do not operate is an example offunction restriction. Subsequently, the process of step S206 is started.

In step S206, the power receiving and supplying unit 103 determinespower to be received (corresponding to power to be received from thepower supply apparatus 200 by the power receiving and supplying unit 103via the VBUS terminal of the connecting unit 101) so that power to bereceived will not exceed the power supply capability of the power supplyapparatus 200 determined in step S203. The power receiving and supplyingunit 103 starts the power receiving operation so as to receive, from thepower supply apparatus 200, power equal to or lower than the powerdetermined in step S206. Subsequently, the process of step S207 isstarted.

In step S207, the power receiving and supplying unit 103 starts thecharging of the power source 102 together with the supplying of powerreceived from the power supply apparatus 200 via the VBUS terminal ofthe connecting unit 101 to the power control unit 104 and the powersource 102.

As described above, if the power supply capability of the power supplyapparatus 200 is not Default USB (NO in step S202), the process of stepS208 is started. In step S208, the system control unit 109 determineswhether the operation power (corresponding to power supplied from thepower control unit 104 to each component to operate the power receivingapparatus 100) is higher than the power supply capability of the powersupply apparatus 200 determined in step S202. If it is determined thatthe operation power is higher than the power supply capability of thepower supply apparatus 200 (YES in step S208), the process of step S209is started. If the operation power is determined to be equal to or lowerthan the power supply capability of the power supply apparatus 200 (NOin step S208), the process of step S210 is started.

In step S209, the system control unit 109 switches the operation mode orrestricts the functions of the power receiving apparatus 100 so that theoperation power (corresponding to power supplied from the power controlunit 104 to each component to operate the power receiving apparatus 100)will be equal to or lower than the power supply capability of the powersupply apparatus 200 determined in step S202. Switching from the imagecapturing mode to the reproduction mode is an example of operation modeswitching. A state in which some or all of the image capturing functionsdo not operate is an example of function restriction. Subsequently, theprocess of step S210 is started.

In step S210, the power receiving and supplying unit 103 determinespower to be received (corresponding to power to be received from thepower supply apparatus 200 by the power receiving and supplying unit 103via the VBUS terminal of the connecting unit 101) so that power to bereceived will not exceed the power supply capability of the power supplyapparatus 200 determined in step S202. The power receiving and supplyingunit 103 starts the power receiving operation so as to receive, from thepower supply apparatus 200, power equal to or lower than the powerdetermined in step S210. Subsequently, the process of step S211 isstarted.

In step S211, the power receiving and supplying unit 103 starts thecharging of the power source 102 together with the supplying of powerreceived from the power supply apparatus 200 via the VBUS terminal ofthe connecting unit 101 to the power control unit 104 and the powersource 102. Subsequently, the process of step S212 is started.

In step S212, the BC device determination unit 108 determines the typeof the power supply apparatus 200 via the D+ terminal and the D−terminal. The BC device determination unit 108 supplies, to the powersupply capability determination unit 106, the information related to thetype of the power supply apparatus 200. The power supply capabilitydetermination unit 106 determines the power supply capability of thepower supply apparatus 200 based on the information related to the typeof the power supply apparatus 200. Subsequently the process of step S213is started.

In step S213, the power supply capability determination unit 106determines whether the power supply capability of the power supplyapparatus 200 has been changed to Default USB. Whether the power supplycapability of the power supply apparatus 200 has been changed to DefaultUSB is determined based on the CC voltage detected by the voltagedetection unit 107. If the CC voltage is equal to or higher than 0.25 Vbut is lower than 0.66 V, the power supply capability determination unit106 will determine that the power supply capability of the power supplyapparatus 200 has been changed to Default USB. If the power supplycapability of the power supply apparatus 200 has been changed to DefaultUSB (YES in step S213), the process of step S214 is started. If thepower supply capability of the power supply apparatus 200 has not beenchanged to Default USB (NO in step S213), the process of step S213 isrepeated.

In step S214, the system control unit 109 determines whether theoperation power (corresponding to power supplied to each component fromthe power control unit 104 to operate the power receiving apparatus 100)is higher than the power supply capability of the power supply apparatus200 determined in step S212. If it is determined that the operationpower is higher than the power supply capability of the power supplyapparatus 200 (YES in step S214), the process of step S215 is started.If it is determined that the operation power is equal to or lower thanthe power supply capability of the power supply apparatus 200 (NO instep S214), the process of step S216 is started.

In step S215, the system control unit 109 switches the operation mode orrestricts the functions of the power receiving apparatus 100 so that theoperation power (corresponding to power supplied from the power controlunit 104 to each component to operate the power receiving apparatus 100)will be equal to or lower than the power supply capability of the powersupply apparatus 200 determined in step S212. Switching from the imagecapturing mode to the reproduction mode is an example of operation modeswitching. A state in which some or all of the image capturing functionsdo not operate is an example of function restriction. Subsequently, theprocess of step S216 is started.

In step S216, the power receiving and supplying unit 103 determinespower to be received (corresponding to power to be received from thepower supply apparatus 200 by the power receiving and supplying unit 103via the VBUS terminal of the connecting unit 101) so that power to bereceived will not exceed the power supply capability of the power supplyapparatus 200 determined in step S212. The power receiving and supplyingunit 103 starts the power receiving operation so as to receive, from thepower supply apparatus 200, power equal to or lower than the powerdetermined in step S216. Subsequently, the processing of the flowchartsshown in FIGS. 2A and 2B ends.

Note that the transition of the power supply capability of the powersupply apparatus 200 to the Default USB is performed in the power supplyapparatus 200. Hence, the power supply apparatus 200 may shift the powersupply capability of the power supply apparatus 200 to the Default USBbefore the process of step S212 is started or while the process of stepS212 is being performed. If the power supply apparatus 200 shifts thepower supply capability of the power supply apparatus 200 to the DefaultUSB before the process of step S212 is started or while the process ofstep S212 is being performed, the system control unit 109 will interruptthe process of step S212. The system control unit 109 will then completethe shutdown processing within 60 ms from the transition of the powersupply capability of the power supply apparatus 200 to the Default USBand will stop receiving power supplied from the power supply apparatus200 to the VBUS terminal of the connecting unit 101. As a result, evenif a state in which the operation of the power receiving apparatus 100stops unexpectedly occurs, the operation of the power receivingapparatus 100 can be stopped safely.

FIG. 3 is a timing chart for illustrating an example of the operation ofthe power receiving apparatus 100 according to the first embodiment.FIG. 3 shows a timing chart corresponding to the operation example ofthe power receiving apparatus 100 from step S212 to step S216.

A transition 301 corresponds to step S213. A transition 302 correspondsto step S216. A period T1 from the transition 301 to the transition 302is defined to be 60 ms or less in accordance with the USB Type-Cstandard.

A process 303 corresponds to the process of step S212. A process 304corresponds to the process of step S215. There is a possibility that aperiod T2 in which the process 303 is performed may exceed 60 ms if theprocess is performed in compliance with the USB BC 1.2 standard. Forexample, if it is set so that the process 303, the process 304, and thetransition 302 will be performed after the transition 301, the period T1may exceed 60 ms and deviate from the USB Type-C standard. Hence, in thefirst embodiment, it is set so that the process 303 will be startedbefore the transition 301.

Note that if the transition 301 has occurred in the period T2 in whichthe process 303 is to be performed, the system control unit 109interrupts the process 303. The system control unit 109 then completesthe shutdown processing in 60 ms or less from the transition 301, andstops receiving power supplied from the power supply apparatus 200 viathe VBUS terminal of the connecting unit 101. As a result, the operationof the power receiving apparatus 100 can be stopped safely even if astate in which the operation of the power receiving apparatus 100 stopsunexpectedly occurs.

As described above, in a case in which the power supply capability ofthe power supply apparatus 200 is determined in compliance with the USBBC2.1 standard, it may require time that exceeds 60 ms. Hence, thefollowing state may occur if the power supply capability of the powersupply apparatus 200 is determined in compliance with the USB BC 1.2standard after the power supply capability of the power supply apparatus200 has been determined to be Default USB based on the CC voltage. Powerwhich is to be supplied from the power supply apparatus 200 to the powerreceiving apparatus 100 via the VBUS terminal of the connecting unit 101may shift to a voltage conforming to Default USB before the process fordetermining the power supply capability of the power supply apparatus200 in compliance with the USB BC 1.2 standard is completed. In thiscase, power supplied from the power supply apparatus 200 to the powerreceiving apparatus 100 via the VBUS terminal will fall below the powerthat the power receiving apparatus 100 will attempt to receive from thepower supply apparatus 200 via the VBUS terminal. If power supplied fromthe power supply apparatus 200 to the power receiving apparatus 100 viathe VBUS terminal falls below the power that the power receivingapparatus 100 will attempt to receive from the power supply apparatus200 via the VBUS terminal, the operation of the power receivingapparatus 100 may stop unexpectedly. In contrast, in the firstembodiment, the power supply capability of the power supply apparatus200 is determined in compliance with the USB BC 1.2 standard before thepower which is to be supplied from the power supply apparatus 200 to thepower receiving apparatus 100 via the VBUS terminal shifts to powerconforming to the Default USB. Hence, according to the first embodiment,it reduces the occurrence of a state in which power to be supplied fromthe power supply apparatus 200 to the power receiving apparatus 100 viathe VBUS terminal will shift to power conforming to the Default USBbefore the process for determining the power supply capability of thepower supply apparatus 200 in compliance with the USB BC 1.2 standard iscompleted. Therefore, according to the first embodiment, it is possibleto reduce the occurrence of a state in which the operation of the powerreceiving apparatus 100 stops unexpectedly.

Note that the embodiments of the disclosure are not limited to the firstembodiment as described above. The embodiments of the disclosure includethe first embodiment that has been changed or modified without departingfrom the scope of the disclosure.

Second Embodiment

Various kinds of functions, processes, or methods described in the firstembodiment can be implemented by a personal computer, a microcomputer, aCPU (Central Processing Unit), a processor, or the like by usingcorresponding programs. In the second embodiment, a personal computer, amicrocomputer, a CPU (Central Processing Unit), a processor, or the likewill be referred to as a “computer X” hereinafter. Also, in the secondembodiment, a program for controlling the computer X, that is, a programfor implementing one of the various kinds of functions, processes, ormethods described in the first embodiment will be referred to as a“program Y”.

Each of the various kinds of functions, processes, or methods describedin the first embodiment is implemented by the computer X executing theprogram Y. In this case, the program Y is supplied to the computer X viaa computer-readable storage medium. The computer-readable storage mediumaccording to the second embodiment includes at least one of a hard diskdevice, a magnetic storage device, an optical storage device, amagneto-optical storage device, a memory card, a volatile memory, anonvolatile memory, or the like. The computer-readable storage mediumaccording to the second embodiment is a non-transitory storage medium.

While aspects of the disclosure are described with reference toexemplary embodiments, it is to be understood that the aspects of thedisclosure are not limited to the exemplary embodiments. The scope ofthe following claims is to be accorded the broadest interpretation so asto encompass all modifications and equivalent structures.

This application claims priority from Japanese Patent Application No.2017-254850, filed Dec. 28, 2017, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An electronic device comprising: a connector thatincludes a VBUS terminal for receiving power from a power supplyapparatus, a CC (configuration channel) terminal, and data communicationterminals; and a determination circuitry that determines a power supplycapability of the power supply apparatus by using the data communicationterminals, before a predetermined transition occurs in the CC terminalin response that the power supply capability of the power supplyapparatus is changed to a predetermined power supply capability.
 2. Theelectronic device according to claim 1, wherein the predetermined powersupply capability conforms to USB (Universal Serial Bus) BatteryCharging standard.
 3. The electronic device according to claim 1,wherein a voltage of the CC terminal before the occurrence of thepredetermined transition is a voltage defined in USB Type-C standard. 4.The electronic device according to claim 1, wherein the determinationcircuitry determines the power supply capability of the power supplyapparatus based on a type of the power supply apparatus which isdetermined via the data communication terminals.
 5. The electronicdevice according to claim 1, further comprising a receiving powercontrol circuitry that controls power to be received from the powersupply apparatus in accordance with the power supply capability of thepower supply apparatus determined by using the data communicationterminals.
 6. A method comprising: receiving power from a power supplyapparatus via a VBUS terminal; and determining a power supply capabilityof the power supply apparatus by using data communication terminals,before a predetermined transition occurs in a CC (configuration channel)terminal in response that the power supply capability of the powersupply apparatus is changed to a predetermined power supply capability.7. A non-transitory storage medium that stores a program causing acomputer to execute a method, the method comprising: receiving powerfrom a power supply apparatus via a VBUS terminal; and determining apower supply capability of the power supply apparatus by using datacommunication terminals, before a predetermined transition occurs in aCC (configuration channel) terminal in response that the power supplycapability of the power supply apparatus is changed to a predeterminedpower supply capability.